More/better comments

A design recipe for Non-blocking forms

Demo_NonBlocking_Form.py

@@ -1,11 +1,48 @@
 import PySimpleGUI as sg
 import time
 
-def main():
-    StatusOutputExample()
-    StatusOutputExample_context_manager()
+
+
 
 # form that doen't block
+# good for applications with an loop that polls hardware
+def StatusOutputExample():
+    # Make a form, but don't use context manager
+    form = sg.FlexForm('Running Timer', auto_size_text=True)
+    # Create a text element that will be updated with status information on the GUI itself
+    output_element = sg.Text('', size=(8, 2), font=('Helvetica', 20))
+    # Create the rows
+    form_rows = [[sg.Text('Non-blocking GUI with updates')],
+                 [output_element],
+                 [sg.SimpleButton('Quit')]]
+    # Layout the rows of the form and perform a read. Indicate the form is non-blocking!
+    form.LayoutAndRead(form_rows, non_blocking=True)
+
+    #
+    # Some place later in your code...
+    # You need to perform a ReadNonBlocking on your form every now and then or
+    # else it won't refresh.
+    #
+    # your program's main loop
+    i=0
+    while (True):
+        # This is the code that reads and updates your window
+        output_element.Update('{:02d}:{:02d}.{:02d}'.format((i // 100) // 60, (i // 100) % 60, i % 100))
+        button, values = form.ReadNonBlocking()
+        if values is None or button == 'Quit':
+            break
+        i += 1
+        # Your code begins here
+        time.sleep(.01)
+
+    # Broke out of main loop. Close the window.
+    form.CloseNonBlockingForm()
+
+
+
+# This design pattern follows the uses a context manager to better control the resources
+# It may not be realistic to use a context manager within an embedded (Pi) environment
+# If on a Pi, then consider the above design patterns instead
 def StatusOutputExample_context_manager():
     with sg.FlexForm('Running Timer', auto_size_text=True) as form:
         output_element = sg.Text('', size=(8, 2), font=('Helvetica', 20))
@@ -24,35 +61,10 @@ def StatusOutputExample_context_manager():
         else:
             form.CloseNonBlockingForm()
 
-
-# form that doen't block
-def StatusOutputExample():
-    # Make a form, but don't use context manager
-    form = sg.FlexForm('Running Timer', auto_size_text=True)
-    # Create a text element that will be updated with status information on the GUI itself
-    output_element = sg.Text('', size=(8, 2), font=('Helvetica', 20))
-    # Create the rows
-    form_rows = [[sg.Text('Non-blocking GUI with updates')],
-                 [output_element],
-                 [sg.SimpleButton('Quit')]]
-    # Layout the rows of the form and perform a read. Indicate the form is non-blocking!
-    form.LayoutAndRead(form_rows, non_blocking=True)
-
-    #
-    # Some place later in your code...
-    # You need to perform a ReadNonBlocking on your form every now and then or
-    # else it won't refresh
-    #
-
-    for i in range(1, 1000):
-        output_element.Update('{:02d}:{:02d}.{:02d}'.format((i // 100) // 60, (i // 100) % 60, i % 100))
-        button, values = form.ReadNonBlocking()
-        if values is None or button == 'Quit':
-            break
-        time.sleep(.01)
-    else:
-        form.CloseNonBlockingForm()
-
+def main():
+    StatusOutputExample()
+    sg.MsgBox('End of non-blocking demonstration')
+    # StatusOutputExample_context_manager()
 
 
 if __name__ == '__main__':